NEAR IZYUM, Ukraine—When Ukraine pushed Russian forces back from the country’s second-largest city of Kharkiv in May, they quickly headed to the border to dig their flag into Ukrainian soil that, for a time, had fallen into Russian hands.
Since then, the front lines in Ukraine’s northeastern region have been largely static. Russian artillery on the other side of the border continues to hammer Ukrainian positions and civilian buildings, and Kyiv has pledged not to target Russian territory with weapons provided by the West.